The interviewer knows that nobody knows how many windows are in Seattle. However, the reason why these kinds of questions get asked is to see how you think on your feet. Do you become flustered? Do you try to answer in a practical way? If you get one of these questions, relax. Take a moment. And try to answer in a logical way.

It doesn’t matter if you’re way off. What matters is that you remained calm, and answered pragmatically.

For instance, estimate how many windows are in Seattle by guessing the population of Seattle. From that infer the number of households and vehicles. And then guess the price of how much it would cost for one window—maybe $10 per window. The rest is simple math. Again, it’s not your answer that matters. It’s how you come about it.